EP1213370A2 - Verfahren und Zusammensetzung zur Reinigung von Turbinenmotorbauteilen - Google Patents

Verfahren und Zusammensetzung zur Reinigung von Turbinenmotorbauteilen Download PDF

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Publication number
EP1213370A2
EP1213370A2 EP01310194A EP01310194A EP1213370A2 EP 1213370 A2 EP1213370 A2 EP 1213370A2 EP 01310194 A EP01310194 A EP 01310194A EP 01310194 A EP01310194 A EP 01310194A EP 1213370 A2 EP1213370 A2 EP 1213370A2
Authority
EP
European Patent Office
Prior art keywords
cleaning
acid
component
solution
acid solution
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP01310194A
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English (en)
French (fr)
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EP1213370A3 (de
Inventor
John Robert Lagraff
D. Sangeeta
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
General Electric Co
Original Assignee
General Electric Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by General Electric Co filed Critical General Electric Co
Publication of EP1213370A2 publication Critical patent/EP1213370A2/de
Publication of EP1213370A3 publication Critical patent/EP1213370A3/de
Withdrawn legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B08—CLEANING
    • B08B—CLEANING IN GENERAL; PREVENTION OF FOULING IN GENERAL
    • B08B3/00—Cleaning by methods involving the use or presence of liquid or steam
    • B08B3/04—Cleaning involving contact with liquid
    • B08B3/10—Cleaning involving contact with liquid with additional treatment of the liquid or of the object being cleaned, e.g. by heat, by electricity or by vibration
    • B08B3/12—Cleaning involving contact with liquid with additional treatment of the liquid or of the object being cleaned, e.g. by heat, by electricity or by vibration by sonic or ultrasonic vibrations
    • C—CHEMISTRY; METALLURGY
    • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
    • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
    • C11D7/00—Compositions of detergents based essentially on non-surface-active compounds
    • C11D7/02—Inorganic compounds
    • C11D7/04—Water-soluble compounds
    • C11D7/08—Acids
    • C—CHEMISTRY; METALLURGY
    • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
    • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
    • C11D7/00—Compositions of detergents based essentially on non-surface-active compounds
    • C11D7/22—Organic compounds
    • C11D7/26—Organic compounds containing oxygen
    • C11D7/265—Carboxylic acids or salts thereof
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23G—CLEANING OR DE-GREASING OF METALLIC MATERIAL BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS
    • C23G1/00—Cleaning or pickling metallic material with solutions or molten salts
    • C23G1/02—Cleaning or pickling metallic material with solutions or molten salts with acid solutions
    • C23G1/10—Other heavy metals
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D25/00—Component parts, details, or accessories, not provided for in, or of interest apart from, other groups
    • F01D25/002—Cleaning of turbomachines
    • C—CHEMISTRY; METALLURGY
    • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
    • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
    • C11D2111/00—Cleaning compositions characterised by the objects to be cleaned; Cleaning compositions characterised by non-standard cleaning or washing processes
    • C11D2111/10—Objects to be cleaned
    • C11D2111/14—Hard surfaces
    • C11D2111/20—Industrial or commercial equipment, e.g. reactors, tubes or engines

Definitions

  • the present invention relates to a method and composition for cleaning a turbine engine component.
  • a typical gas turbine engine includes a compressor, a combustor and a turbine. Compressed gases emerging from the compressor are mixed with fuel and burned in the combustor. Hot products of the combustion emerge from the combustor at high pressure and enter the turbine where thrust is produced to propel the engine and to drive the turbine, which in turn drives the compressor.
  • the compressor and the turbine include alternating rows of rotating and stationary coated airfoils.
  • High temperature combustion gases degrade the coatings through hot corrosion or oxidation.
  • Gases that circulate through the airfoils, particularly during operation on the ground, also include contaminants such as dirt that has been ingested by the engine. Dirt accumulation can cause serious damage at high engine operating temperatures. Accumulation of dirt can impede effective cooling and if melted, can infiltrate and destroy protective coatings.
  • the dirt typically comprises mixtures of Ca, Mg, Al, Si, Ni and Fe carbonates and oxides such as multi-elemental spinels (AB 2 O 4 ).
  • a low melting point eutectic Ca 3 Mg 4 Al 2 Si 9 O 30 , (CMAS) similar in composition to diopside, can form from silicate-containing dirts at engine temperatures near 1200°C and can wet and infiltrate coatings leading to crack formation and component failure.
  • TGOs thermally grown oxides
  • alumina scales which form on metallic MCrAIY coatings impede chemical attack during stripping, thus leading to incomplete coating removal or excessive base metal attack, which can necessitate rework or cause component destruction.
  • a turbine engine component can be periodically cleaned to remove dirt or the component can be periodically removed from service for repair, which requires a series of cleaning and stripping steps. These steps should remove deposited dirt and strip coating material without adversely attacking the component base metal alloy.
  • Grit blasting is a common method to clean dirt and remove coatings. Unfortunately, grit blasting does not clean dirty or blocked internal passageways. Grit blasting can damage the base alloy thereby thinning airfoil walls. Also, grit blasting may lodge particulates in cracks, where they can impede welding and brazing or in the surface where they can become incorporated into new coatings creating structurally weak regions.
  • Chemical solutions have been used for cleaning dirt and stripping coatings from gas turbine components. However, these chemical solutions are typically composed of combinations of strong fuming mineral acids or caustic bases. The solutions are often required to include precise amounts of additives such as oxidizers or surfactants. These solutions can require a dedicated (and expensive) chemical facility, including complicated and expensive chemical lines with vents, scrubbers and complex process monitoring equipment.
  • the invention is a method for cleaning an engine component.
  • an engine component is provided and is immersed in an acid solution selected from phosphoric acid, citric acid and acetic acid.
  • the invention is a cleaning composition for an engine component, comprising an agitated acid solution selected from phosphoric acid, citric acid and acetic acid.
  • the invention provides three benign acid compositions - citric acid, acetic acid and phosphoric acid - that effectively remove deposited dirt from engine components with little if any base metal attack. These solutions are non-fuming, have little if any exposure limits, possess broad composition windows for easy solution monitoring and in the case of citric and acetic acid can be disposed of through solution evaporation and burn-off. Also, phosphoric acid is both a cleaning composition and a stripping composition. Phosphoric acid can remove alumina-based TGOs and aluminide coatings down to base metal.
  • FIG. 1 is a schematic cross-sections of a turbine component alloy with a corrosion resistant aluminide coating with deposited dirt and thermally grown oxides (TGOs).
  • FIG. 2 is a top view of the component, showing internal cooling passageways. Grit blasting techniques for cleaning the alloy are ineffective to clean the passageways. The compositions of the invention penetrate and clean these passageways.
  • FIG 3 is a schematic cross-sectional view of a CMAS coated Hast-X button used for screening and optimization of various chemical cleaning compositions. The CMAS simulates dirt found on real engine components. Measuring the mass of CMAS removed yields cleaning efficiency of a particular chemical cleaning system.
  • FIG. 4 is a schematic representation of the method 10 of the invention.
  • a dirtied engine component is provided 12, for example by removing a turbine engine from on-line duty and disassembling the engine into a component such as the nozzle.
  • the component is immersed 14 in an acid solution for cleaning.
  • the acid solution can be agitated during immersing for example by stirring or by the application of ultrasonics.
  • the component is then rinsed 16, for example by immersion in deionized water.
  • ultrasonic agitation can be applied during the rinsing step16.
  • the Example demonstrates effective cleaning of airfoil surfaces without damaging underlying metal.
  • a variety of chemical cleaning systems were evaluated for their dirt removal capability from stage 1 nozzles. The screening was conducted on control specimens consisting of 35 mil thick Ni-based Hast-X buttons coated with a plasma sprayed simulated dirt composition (oxides of Ca-Mg-Al-Si (CMAS)). The CMAS coatings were amorphous as determined by x-ray diffraction analysis. The CMAS buttons were used to test a variety of process parameters, i.e., time, temperature and concentration. The chemical systems were also tested using scrap pieces of nozzles (PS) and blades (AE).
  • PS scrap pieces of nozzles
  • AE blades
  • Solutions were prepared from reagent grade stock solutions mixed with house deionized (DI) water except for a Versene® solution (chelating and sequestering agent) and a Plurafac® surfactant.P (a polyoxyalkylene condensate). Cleaning procedures were carried out in glass beakers placed on magnetically stirred hot-plates. Temperature was controlled to within ⁇ 5°C and was monitored by thermometers placed about 1/2 inch from the bottom of each glass beaker. CMAS buttons and scrap components were suspended in Al foil covered beakers in Monel® (nickel alloy) mesh baskets.
  • DI house deionized
  • Plurafac® surfactant.P a polyoxyalkylene condensate
  • Cleaning efficiency of a chemical system was determined by measuring the mass of the CMAS coating before and after cleaning.
  • the plasma spray process itself forms a thin TGO layer between the base alloy and CMAS (see schematic FIG. 3).
  • the TGO layer affects weight loss measurement by about 5-10%.
  • a base alloy's resistance to chemical attack was determined from pieces of GTD-222 alloy, which were included during each screening experiment. These alloy pieces were mounted, polished and inspected optically for intergranular attack (IGA) and other indications of chemical reaction.
  • IGA intergranular attack
  • FIG. 5 shows percent weight loss of CMAS as a function of time (10 and 60 minutes) at 50°C except for Versene® solution cleaning at 85°C. 100 percent weight loss indicates complete CMAS coating removal, while greater than 100 percent loss indicates base alloy attack.
  • Base alloy stability was determined by including pieces of GTD-222 buttons with each of the chemical cleaning runs. While none of the buttons exhibited detectable loss of mass, the piece included in the H 2 SO 4 run (50°C, 60 minutes) exhibited grain etching. Cross sections of each of the GTD-222 pieces were polished and inspected by optical microscopy. No evidence of pitting, reaction or grain boundary attack was observed for any of the chemical cleaning systems. However, it was determined from the weight loss data of FIG. 5, that methanesulfonic acid (MSA) and sulfuric acid mildly attacked the HastX buttons.
  • MSA methanesulfonic acid
  • buttons exhibited a white residue after chemical cleaning.
  • the composition of the white residue was analyzed by x-ray diffraction to be mostly CaSO 4 .
  • the cleaning residue was completely removed by rinsing in an ultrasonic bath following chemical cleaning with magnetic stirring only.
  • This Example illustrates effect of concentration, temperature and time with respect to citric acid cleaning efficiency.
  • FIG. 6 is a resulting main effects plot determined by a Box-Benken design of experiment (DOE) for citric acid.
  • DOE Box-Benken design of experiment
  • a broad temperature range can be about room temperature to about the solution boiling point, desirably about 40 to about 80°C and preferably about 50 to about 70°C.
  • Concentration can be about 0.1 to about 6 M, desirably about 1 to about 5 M and preferably about 2 to about 4 M.
  • Contact time can be about 0.5 to about 48 hours, desirably about 1 to about 24 hours and preferably about 4 to about 8 hours.
  • FIG. 7 is a resulting main effects plot for phosphoric acid.
  • FIG. 7 shows percent weight loss of CMAS for phosphoric acid as a function of concentration, temperature and time (15%, 29% and 40% by weight of 85% H3P04 solution corresponds to 1M, 3M & 5M).
  • a broad temperature range can be about room temperature to about the solution boiling point, desirably about 40 to about 80°C and preferably about 50 to about 70°C.
  • Concentration can be about 0.1 to about 8 M, desirably about 1 to about 7 M and preferably about 3 to about 5 M.
  • Contact time can be about 0.5 to about 48 hours, desirably about 1 to about 24 hours and preferably about 4 to about 8 hours.
  • This EXAMPLE illustrates cleaning of turbine engine components.
  • Button sections of nozzle trailing edges were cleaned at 50°C for 60 minutes in three acid solutions (citric, MSA, and phosphoric) along with corresponding CMAS control buttons. All three systems removed 100% of CMAS coatings on control buttons. After chemical cleaning, the nozzle sections weighed less and were visibly cleaner as indicated in the following TABLE 1.
  • Solution Sample Type CMAS/dirt removed Ultrasonicate button 0 mg in water nozzle 0 mg 5M Citric botton 29.5 mg (90%) nozzle 45.6 mg MSA button 29.9 mg (45%) Nozzle 54.1 mg 5M H 3 PO 4 button 29.9 mg (40%) nozzle 39.2 mg
  • FIG. 8 is optical micrographs of cross-sections of cooling holes on the trailing edges of nozzles for components cleaned in water (FIG. 8), citric acid (FIG. 9), phosphoric acid (FIG. 10) and MSA (FIG. 11).
  • Citric acid, MSA and phosphoric acid removed material from both exterior surface and internal cooling holes.
  • Phosphoric acid and MSA removed more dirt and thermally grown oxide from the cooling holes.
  • the phosphoric acid, MSA and citric acid cleaned nozzle components revealed approximately equal weight loss. However, the phosphoric acid and MSA chemical components appeared cleaner particularly in the cooling holes.
  • FIG. 12 and FIG. 13 show rate of CMAS coating loss as a function of either stirring or applying ultrasonics to a phosphoric acid or citric acid cleaning solution. Ultrasonics during the cleaning step removes the CMAS coating at a more rapid rate than simply immersing the button in a stirred solution.
  • Equation (1) The reaction rate for the phosphoric acid cleaning system follows a first order kinetic model according to Equation (1).
  • the reaction constants K, for ultrasonic cleaning and cleaning in a stirred solution are respectively -0.44 and -0.24 sec -1 . Ultrasonic cleaning is almost a factor of two quicker than only stirring the phosphoric acid solution.
  • Equation (2) The reaction rate for the citric acid system follows zero-order kinetics typical of a surface reaction limited process according to Equation (2).
  • the reaction constants for citric acid for ultrasonic cleaning and stirred solution cleaning were 9.0 and 2.6 sec -1 , respectively.
  • the constant for ultrasonic cleaning represents an almost four-fold increase in cleaning rate. Such an increase is unexpected in a surface reaction limited process.
  • the EXAMPLES show two chemical systems that can be used for cleaning optimization--an inorganic phosphoric acid, an organic citric acid and an organic acetic acid. Both phosphoric acid and citric acid systems readily removed CMAS coatings without visible base metal attack.
  • Acetic acid was also shown to be an effective chemical system for cleaning optimization.
  • a broad temperature range can be about room temperature to about the solution boiling point, desirably about 40 to about 80°C and preferably about 50 to about 70°C.
  • Concentration can be about 0.1 to about 8 M, desirably about 1 to about 7 M and preferably about 3 to about 5 M.
  • Contact time can be about 0.5 to about 48 hours, desirably about 1 to about 24 hours and preferably about 4 to about 8 hours.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Organic Chemistry (AREA)
  • Mechanical Engineering (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Wood Science & Technology (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Materials Engineering (AREA)
  • Emergency Medicine (AREA)
  • General Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Inorganic Chemistry (AREA)
  • Metallurgy (AREA)
  • General Engineering & Computer Science (AREA)
  • Cleaning By Liquid Or Steam (AREA)
  • Cleaning And De-Greasing Of Metallic Materials By Chemical Methods (AREA)
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EP01310194A 2000-12-05 2001-12-05 Verfahren und Zusammensetzung zur Reinigung von Turbinenmotorbauteilen Withdrawn EP1213370A3 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US09/729,324 US20020103093A1 (en) 2000-12-05 2000-12-05 Method and composition for cleaning a turbine engine component
US729324 2000-12-05

Publications (2)

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EP1213370A2 true EP1213370A2 (de) 2002-06-12
EP1213370A3 EP1213370A3 (de) 2002-11-27

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US (2) US20020103093A1 (de)
EP (1) EP1213370A3 (de)
BR (1) BR0105903A (de)
CA (1) CA2363613A1 (de)
SG (1) SG97226A1 (de)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1411149A1 (de) * 2002-10-18 2004-04-21 Siemens Aktiengesellschaft Verfahren zum Entfernen eines Schichtbereichs eines Bauteils
EP2127764A1 (de) * 2008-05-27 2009-12-02 Siemens Aktiengesellschaft Verfahren und Vorrichtung zur Reinigung eines Hochtemperaturbauteils

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US20070023142A1 (en) * 2002-12-19 2007-02-01 Lagraff John R Airfoil refurbishment method
DE102004045297A1 (de) * 2004-09-16 2006-03-23 Basf Ag Verfahren zum Behandeln von metallischen Oberflächen unter Verwendung von Formulierungen auf Basis von wasserarmer Methansulfonsäure
US7531048B2 (en) * 2004-10-19 2009-05-12 Honeywell International Inc. On-wing combustor cleaning using direct insertion nozzle, wash agent, and procedure
GB2439336A (en) * 2006-06-24 2007-12-27 Siemens Ag Ultrasonic cleaning of engine components
US7578178B2 (en) * 2007-09-28 2009-08-25 United Technologies Corporation Method of inspecting turbine internal cooling features using non-contact scanners
WO2009065449A2 (de) * 2007-11-23 2009-05-28 Siemens Aktiengesellschaft Verfahren und vorrichtung zur reinigung eines hochtemperaturbauteils mit grossen abmassen
US20090133712A1 (en) * 2007-11-26 2009-05-28 General Electric Company Methods for cleaning generator coils
US8876978B2 (en) * 2008-02-14 2014-11-04 Mitsubishi Heavy Industries, Ltd. Method for regenerating gas turbine blade and gas turbine blade regenerating apparatus
US7829513B2 (en) * 2009-03-12 2010-11-09 Greenology Products, Inc. Organic cleaning composition
US20110083701A1 (en) * 2009-10-09 2011-04-14 General Electric Company Process to clean gas turbine fuel chamber components
US20120168320A1 (en) * 2010-12-30 2012-07-05 Monique Chauntia Bland System and method for scale removal from a nickel-based superalloy component
US9458418B2 (en) 2012-05-31 2016-10-04 George A. Gorra All natural dishwashing composition comprising lemon powder, vinegar powder, and salt
US9453186B2 (en) 2012-05-31 2016-09-27 George A. Gorra All natural dishwashing composition comprising lemon powder and vinegar powder
WO2014028517A1 (en) * 2012-08-17 2014-02-20 Idev Technologies, Inc. Surface oxide removal methods
JP6395732B2 (ja) * 2013-03-01 2018-09-26 ゼネラル・エレクトリック・カンパニイ ガスタービン空気圧縮機での腐食を防止するための組成物及び方法
US20150159122A1 (en) * 2013-12-09 2015-06-11 General Electric Company Cleaning solution and methods of cleaning a turbine engine
US9926517B2 (en) 2013-12-09 2018-03-27 General Electric Company Cleaning solution and methods of cleaning a turbine engine
US9932854B1 (en) 2013-12-09 2018-04-03 General Electric Company Methods of cleaning a hot gas flowpath component of a turbine engine
US20150198059A1 (en) * 2014-01-10 2015-07-16 General Electric Company Gas turbine manual cleaning and passivation
CN103758640B (zh) * 2014-01-27 2016-03-02 陈凤鸣 一种三元催化器免拆清洗方法
BR102016021259B1 (pt) 2015-10-05 2022-06-14 General Electric Company Método e soluções de limpeza de um motor de turbina e composição de reagente
US10569309B2 (en) * 2015-12-15 2020-02-25 General Electric Company Equipment cleaning system and method
US10428683B2 (en) 2016-01-05 2019-10-01 General Electric Company Abrasive gel detergent for cleaning gas turbine engine components
US10005111B2 (en) 2016-01-25 2018-06-26 General Electric Company Turbine engine cleaning systems and methods
US10731508B2 (en) 2017-03-07 2020-08-04 General Electric Company Method for cleaning components of a turbine engine
US10830093B2 (en) 2017-06-13 2020-11-10 General Electric Company System and methods for selective cleaning of turbine engine components

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1411149A1 (de) * 2002-10-18 2004-04-21 Siemens Aktiengesellschaft Verfahren zum Entfernen eines Schichtbereichs eines Bauteils
WO2004038068A1 (de) * 2002-10-18 2004-05-06 Siemens Aktiengesellschaft Verfahren zum entfernen eines schichtbereichs eines bauteils
EP1752562A1 (de) * 2002-10-18 2007-02-14 Siemens Aktiengesellschaft Verfahren zum Entfernen eines Schichtbereichs eines Bauteils
EP2127764A1 (de) * 2008-05-27 2009-12-02 Siemens Aktiengesellschaft Verfahren und Vorrichtung zur Reinigung eines Hochtemperaturbauteils

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SG97226A1 (en) 2003-07-18
US20030050204A1 (en) 2003-03-13
US20020103093A1 (en) 2002-08-01
BR0105903A (pt) 2002-08-13
EP1213370A3 (de) 2002-11-27
CA2363613A1 (en) 2002-06-05

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